## Search found 22 matches

Sun Jul 30, 2017 11:29 pm
Forum: Non-Equilibrium Conditions & The Reaction Quotient
Topic: Reaction Quotient
Replies: 10
Views: 465

### Re: Reaction Quotient

The reaction quotient (Q) is similar to the equilibrium constant (K), but K is the constant when the reaction is in equilibrium while Q is for any stage of the reaction except when it is at equilibrium.
Sun Jul 30, 2017 11:26 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Example from Pg 134 in Course Reader
Replies: 1
Views: 264

### Re: Example from Pg 134 in Course Reader

KP = PPCl3 PCl2 / PPCl5
KP (PPCl5 / PCl2) = PPCl3 (PCl2 / PPCl5)(PPCl5 / PCl2)
KP PPCl5 / PCl2 = PPCl3
Sun Jul 30, 2017 7:48 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Change
Replies: 2
Views: 286

### Re: Change

Because the reactants are being used to make the product, the equilibrium concentration of the reactants would be less than the initial while the product's equilibrium concentration would be higher than its initial. Since we don't know the amount of reactants used to make the product, we would put i...
Sun Jul 30, 2017 7:42 pm
Forum: Acidity & Basicity Constants and The Conjugate Seesaw
Topic: Ka and Kb values
Replies: 3
Views: 390

### Re: Ka and Kb values

They will probably be given.
Sat Jul 22, 2017 10:52 pm
Forum: Hybridization
Topic: Question 4.39 [ENDORSED]
Replies: 4
Views: 487

### Re: Question 4.39[ENDORSED]

P4 is nonpolar because the 4 P atoms are arranged about a center of symmetry and they have the same electronegativity.
Sat Jul 22, 2017 10:43 pm
Forum: Equilibrium Constants & Calculating Concentrations
Topic: Positive Concentrations
Replies: 1
Views: 198

### Re: Positive Concentrations

Yes, but you should still try plugging in both numbers just to make sure. :)
Sat Jul 22, 2017 4:18 pm
Forum: Hybridization
Topic: HW Problem 4.77
Replies: 3
Views: 424

### Re: HW Problem 4.77

We skipped molecular orbital theory so I don't think we have to do this problem.
Sat Jul 22, 2017 4:11 pm
Forum: Hybridization
Topic: Homework Problem 4.43
Replies: 2
Views: 428

### Re: Homework Problem 4.43

Sat Jul 22, 2017 1:59 pm
Forum: Student Social/Study Group
Topic: Post All Chemistry Jokes Here
Replies: 8543
Views: 1473895

### Re: Post All Chemistry Jokes Here

Sat Jul 15, 2017 7:06 pm
Forum: *Molecular Orbital Theory (Bond Order, Diamagnetism, Paramagnetism)
Topic: Relationship between Electronegativity and Orbital Energy
Replies: 4
Views: 1608

### Re: Relationship between Electronegativity and Orbital Energy

Electronegativity is directly proportional to effective nuclear charge, so when electronegativity is high, the nuclear charge is high as well. The high nuclear charge strongly attracts the electrons and pulls them in, decreasing the energy of the orbitals.
Sat Jul 15, 2017 3:58 pm
Forum: Lewis Structures
Topic: Octet Rule [ENDORSED]
Replies: 9
Views: 1050

### Re: Octet Rule[ENDORSED]

One exception to the octet rule would be when atoms exceed their octet. Starting from phosphorus in period 3, atoms can utilize their d subshell in bonding.
Sat Jul 15, 2017 3:54 pm
Forum: Ionic & Covalent Bonds
Topic: The use of hidden d orbital
Replies: 2
Views: 306

### Re: The use of hidden d orbital

In molecules like $SO_{4}^{2-}$ in which sulfur exceeds its octet, the remaining electrons would go into the d orbitals, which should be filled in the same way the s and p orbitals are filled using the Pauli exclusion principle and Hund's rule.
Sat Jul 15, 2017 2:44 pm
Forum: Determining Molecular Shape (VSEPR)
Topic: Naming Compounds
Replies: 1
Views: 273

### Re: Naming Compounds

I suppose the arrangement containing the lone pairs is called the electron geometry and the actual shape of the molecule is called the molecular geometry. This is a great simulation that shows both the electron and molecular geometry: https://phet.colorado.edu/sims/html/molecule-shapes/latest/molecu...
Sat Jul 08, 2017 5:24 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Ground state vs. excited state
Replies: 3
Views: 27699

### Re: Ground state vs. excited state

The ground state electron configuration of an element is the same as the regular configuration in which the electrons are in the lowest possible energy state. For example, the ground state electron configuration of oxygen is 1s2 2s2 2p4. The excited state electron configuration shows when an electro...
Sat Jul 08, 2017 4:56 pm
Forum: Wave Functions and s-, p-, d-, f- Orbitals
Topic: Graphs on page 44 of the textbook
Replies: 1
Views: 310

### Re: Graphs on page 44 of the textbook

This isn't a complete explanation but here's a list of what I have observed from looking at these graphs. The radial distribution function equals zero when ever the radius is equal to zero, signifying that the probability of finding an electron at the nucleus is zero. It can be seen that radii of th...
Sat Jul 08, 2017 4:20 pm
Forum: Trends in The Periodic Table
Topic: Question 2.81
Replies: 1
Views: 441

### Re: Question 2.81

The electron configuration of nitrogen is 1s2 2s2 2p3, which shows that each p-orbital contains one electron. However, the electron configuration of oxygen is 1s2 2s2 2p4, which shows that the px orbital contains two electrons. This leads to electron-electron repulsion which causes instability and m...
Sat Jul 08, 2017 3:46 pm
Forum: Bond Lengths & Energies
Topic: ionization energy
Replies: 2
Views: 414

### Re: ionization energy

Na has a smaller first ionization energy than Al because Al has a greater nuclear charge than Na, which causes the electrons to be more attracted to the center. Also, ionization energy tends to decrease down a group and increase across a period. The first ionization energy is the amount of energy it...
Sun Jul 02, 2017 7:17 pm
Forum: DeBroglie Equation
Replies: 4
Views: 678

Oh, I thought you were asking about part C. You would use $\lambda =\frac{h}{p}$ to solve for the wavelength. How did you get E=vh/λ ?
Sat Jul 01, 2017 10:50 pm
Forum: DeBroglie Equation
Replies: 4
Views: 678

The question doesn't ask for the wavelength of an ejected electron. It asks for the wavelength of the photon that caused the ejection of an electron.
Sat Jul 01, 2017 3:49 pm
Forum: Molarity, Solutions, Dilutions
Topic: Problem E.15 in Fundamentals
Replies: 3
Views: 472

### Re: Problem E.15 in Fundamentals

Find the molar mass of the unknown element M by subtracting the mass of the hydrogen and the oxygen atoms from the given molar mass of the molecule: 74.10 - 2(1.008 + 15.999) = 40.086 g/mol This molar mass is the closest to the molar mass of Calcium, so we can assume that M is calcium. Calcium sulfi...
Sat Jul 01, 2017 3:35 pm
Forum: DeBroglie Equation
Topic: Question about 1.33 Part C
Replies: 1
Views: 417

### Re: Question about 1.33 Part C

Use E\left ( photon \right )=E\left ( threshold \right )+E_{k} Find the energy of the photon: E\left ( photon \right )=E\left ( threshold \right )+\frac{1}{2}m_{e}v_{e}^{2} E\left ( photon \right )=\left ( 1.66\times 10^{-17} J\right )+\frac{1}{2}\left...
Sat Jul 01, 2017 1:37 pm
Forum: Empirical & Molecular Formulas
Topic: Whole Number Coefficients
Replies: 5
Views: 657

### Re: Whole Number Coefficients

You can also convert them to fractions and multiply by the denominator.

For example, you can convert 1.666 to $\frac{5}{3}$ and multiply by 3 to get 5.